Perfuming ingredients of the floral and/or anis type

ABSTRACT

The present invention concerns a compound of formula wherein R represents a hydrogen atom or a C 1-2  alkyl or alkoxyl group; each R 1 , R 2  or R 3  represents a hydrogen atom or a methyl or ethyl group; and X represents a CHO, COOR 4  or CN group, R 4  being a methyl or ethyl group; and at least one of said R, R 1  or R 2  represents a group containing at least one carbon atom; and it use as perfuming ingredient, for instance to impart odor notes of the floral and/or anis type.

TECHNICAL FIELD

The present invention relates to the field of perfumery. Moreparticularly, it concerns the use as perfuming ingredient of a compoundof formula

wherein X represents a CHO, COOR⁴ or CN group, R⁴ being a methyl orethyl group, and at least one of said R, R¹ or R² represents a groupcontaining at least one carbon atom.

The present invention concerns also the use of said compound in theperfumery industry as well as the compositions or articles containingsaid compound, and some of said compounds.

PRIOR ART

To the best of our knowledge, none of the invention's compounds havebeen described as perfuming ingredients.

The closest analogues known in the prior art as perfuming ingredientsare 3-methyl-5-phenylpentanal and 3-methyl-5-phenyl-1-pentanol (seebelow). However, said compounds do not possess a carbon-carbon doublebond in the chain and have a substitution pattern substantiallydifferent, not to mention the fact that the odors are totally different.

One may also cite the compound 5-phenyl-2-pentenal (U.S. Pat. No.3,862,340), which has a structure close to the one of formula (I).However, this compound is reported only as flavor ingredient, i.e. fortotally different use.

Amongst the claimed compounds only 4-methyl-5-phenyl-4-pentenenitrile(see C. C. Wang et al, in J.A.C.S., 2002, 124, 9696),2,4-dimethyl-5-phenyl-4-pentenal (see C. C. Wang et al, in J.A.C.S.,2007, 129, 12032), 4-methyl-5-phenyl-4-penten-1-ol (see A. J. Chalk, etal, in J.O.C. 1976, 41, 1206), 4-methyl-5-phenyl-4-pentenal (see P. H.Dixneuf et al, in J.C.S. Chem. Commun. 1994, 2551-2),4-(phenylmethylene)-1-hexanol (see O. Fujimura et al, in J.A.C.S. 1995,117, 2355), ethyl 4-methyl-5-phenyl-4-pentenoate (see WO 99/61414) areknown, and are all reported as simple chemical compounds. None of theseprior art documents reports or suggests any organoleptic properties ofthe compounds of formula (I), or any use of said compounds in the fieldof perfumery.

DESCRIPTION OF THE INVENTION

We have now surprisingly discovered that a compound of formula

wherein R is an ortho, meta or para substituent of the phenyl, andrepresents a hydrogen atom or a C₁₋₂ alkyl or alkoxyl group;

R¹ represents a hydrogen atom or a C₁₋₃ alkyl group;

R² represents a hydrogen atom or a methyl or ethyl group;

R³ represents a hydrogen atom or a methyl or ethyl group; and

X represents a CHO, COOR⁴ or CN group, R⁴ being a methyl or ethyl group;and

at least one of said R, R¹ or R² represents a group containing at leastone carbon atom,

and said compound being in the form of a E or Z isomer or of a mixturethereof; can be used as perfuming ingredient, for instance to impartodor notes of the floral and/or anis type.

According to a particular embodiment of the invention, said invention'scompounds are those wherein at least two of said R, R¹ or R² representsa group containing at least one carbon atom.

According to a particular embodiment of the invention, said compounds(I) are those wherein R is an ortho, meta or para substituent of thephenyl ring and represent a hydrogen atom or a methyl or ethyl group;

R¹ represents a methyl or ethyl group;R² represents a hydrogen atom or a methyl or ethyl group;R³ represents a hydrogen atom or a methyl or ethyl group; andX represents a CHO, COOR⁴ or CN group, R⁴ being a methyl or ethyl group.

According to another particular embodiment of the invention, saidcompounds (I) are those wherein R is an ortho, meta or para substituentof the phenyl ring and represents a hydrogen atom or a methyl or ethylgroup;

R¹ represents a methyl or ethyl group;R² represents a hydrogen atom or a methyl or ethyl group;R³ represents a hydrogen atom or a methyl or ethyl group; andX represents a CHO, COOR⁴ or CN group, R⁴ being a methyl or ethyl group;andat least one of said R, R² or R³ represents a methyl or ethyl group, inparticular R or R³ represents a methyl or ethyl group.

According to any one of the above embodiments of the invention, saidcompounds (I) are those wherein X represents a CHO group.

According to any one of the above embodiments of the invention, saidcompounds (I) are those wherein each R, R² or R³ represents a hydrogenatom or methyl group, and/or R¹ represents a methyl group.

The compounds of formula

-   -   wherein R^(1′) represents a hydrogen atom or a methyl group, Y        represents a CH₂OH group or a group X, and X, R, R² and R³ have        the same meaning as in any one of the above embodiments; said        compound being in the form of a E or Z isomer or of a mixture        thereof;        are also novel compounds, with the exception of        4-methyl-5-phenyl-4-pentenenitrile,        2,4-dimethyl-5-phenyl-4-pentenal,        4-methyl-5-phenyl-4-penten-1-ol, 4-methyl-5-phenyl-4-pentenal,        ethyl 4-methyl-5-phenyl-4-pentenoate and        4-(phenylmethylene)-1-hexanol. The compounds wherein Y is CH₂OH        are included as useful intermediates for the preparation of all        the other invention's compounds, as it will be seen further        below.

Said compound of formula (II) is also another object of the presentinvention.

Furthermore, since the invention's compounds have a carbon-carbon doublebond, said compounds can be in the form of a E or Z isomer or of amixture thereof. According to any one of the above embodiments of theinvention, said compounds (I) or (II) are those which are in the form ofmixture of E and Z isomers and the E isomer accounts for at least 75%w/w of said mixture, or even at least 88%, or even at least 95%.

According to any one of the above embodiments of the invention, saidcompounds (I) or (II) are those wherein the R group is methyl or ethylgroup.

According to any one of the above embodiments of the invention, saidcompounds (I) or (II) are those wherein the R group is a para, meta orortho substituent, and in particular is a para or meta substituent, orof a mixture thereof. According to any one of the above embodiments ofthe invention, said compounds (I) are those which are in the form ofmixture of para or meta substituent and the para substituent accountsfor at least 90% w/w of said mixture, or even at least 95%.

According to a particular embodiment of the invention, said invention'scompounds of formula (I) or (II) are those having 13 or 14 carbon atomsin total.

As specific examples of the invention's compounds, one may cite, asnon-limiting example, (4E)-4-methyl-5-(4-methylphenyl)-4-pentenal, whichpossesses a very nice lily of the valley note together withpowdery-anisic notes, as well as watery aspects, almost a perfume on itsown. The odor of this compound can be also described as having anelegant lily of the valley/mimosa duality. The overall odor reminds ofthe known ingredient 3-(4-isopropylphenyl)-2-methylpropanal.

As other example one may cite(4E)-2,4-dimethyl-5-(4-methylphenyl)-4-pentenal, which in addition tothe lily of the valley and powdery-anis note possesses also aldehydicnotes as well as natural almond and creamy aspects, with bottom notesreminding of linden or verbena.

As other specific, but non-limiting, examples of the invention'scompounds, one may cite the following ones in Table 1:

TABLE 1 Invention's compounds and their odor properties Compoundstructure and name Odor

Compared to its para isomer described above, this compounddifferentiates himself by being less mimosa and powdery, although beingoverall more powerful

Lily of the valley, very floral, with a sweet and slightly smokedaspect, possesses a good radiance

Linden, watery, aldehydic odor

Lily of the valley, anisic odor

Powerful and nice lily of the valley, green, aldehydic odor

Watery, aldehydic, lily of the valley odor

Benzoic, orange flower, mimosa, anis, natural odor

Anisic, lily of the valley odor

Mimosa, anisic, amaretti odor

Similar to its isomer (4E)-4-methyl-5-(4- methylphenyl)-4-pentenal, butpossessing also an aldehydic and cherry note

Floral, aldehydic

Similar to (4E)-4-methyl-5-(4-methylphenyl)-4- pentenal, but possessingalso an aldehydic note

Anisic, nitrile, floral

According to a particular embodiment of the invention, the compounds offormula (I) are: (4E)-4-methyl-5-(4-methylphenyl)-4-pentenal,(4E)-2,4-dimethyl-5-(4-methylphenyl)-4-pentenal,2,4-dimethyl-5-phenyl-4-pentenal, 4-methyl-5-phenyl-4-hexenal,4-methyl-5-phenyl-4-pentenal or methyl(4E)-4-methyl-5-(4-methylphenyl)-4-pentenoate.

As can be seen, from the above table, although the precise tonalities ofthe invention's compounds may vary according to the exact structure ofthe compounds, the invention's compounds are characterized by floralnotes, and in particular notes of the lily of the valley, mimosa and/oranisic type, frequently together with watery and/or powdery aspect.

This combination of lily/mimosa/anis characters is typical of theinvention's compounds odors and distinguish said compounds from those ofthe prior art having a similar structure and being known as perfumingingredients. Indeed, Mefranal® (3-methyl-5-phenylpentanal from Quest) ischaracterized by a typical lemon, citronella odor, absent from theinvention's compounds, while 3-methyl-5-phenyl-1-pentanol (ArctanderN^(o) 2200) is characterized by an herbaceous, dry odor with woodyundernotes, which is also very different from the odor of the presentcompounds (I).

As mentioned above, the invention concerns the use of a compound offormula (I) as perfuming ingredient. In other words it concerns a methodto confer, enhance, improve or modify the odor properties of a perfumingcomposition or of a perfumed article, which method comprises adding tosaid composition or article an effective amount of at least a compoundof formula (I). By “use of a compound of formula (I)” it has to beunderstood here also the use of any composition containing compound (I)and which can be advantageously employed in perfumery industry as activeingredients.

Said compositions, which in fact can be advantageously employed asperfuming ingredient, are also an object of the present invention.

Therefore, another object of the present invention is a perfumingcomposition comprising:

-   i) as perfuming ingredient, at least one invention's compound as    defined above;-   ii) at least one ingredient selected from the group consisting of a    perfumery carrier and a perfumery base; and-   iii) optionally at least one perfumery adjuvant.

By “perfumery carrier” we mean here a material which is practicallyneutral from a perfumery point of view, i.e. that does not significantlyalter the organoleptic properties of perfuming ingredients. Said carriermay be a liquid or a solid.

As liquid carrier one may cite, as non-limiting examples, an emulsifyingsystem, i.e. a solvent and a surfactant system, or a solvent commonlyused in perfumery. A detailed description of the nature and type ofsolvents commonly used in perfumery cannot be exhaustive. However, onecan cite as non-limiting example solvents such as dipropyleneglycol,diethyl phthalate, isopropyl myristate, benzyl benzoate,2-(2-ethoxyethoxy)-1-ethanol or ethyl citrate, which are the mostcommonly used.

As solid carrier one may cite, as non-limiting examples, absorbing gumsor polymers, or yet encapsulating materials. Examples of such materialsmay comprise wall-forming and plasticizing materials, such as mono, di-or trisaccharides, natural or modified starches, hydrocolloids,cellulose derivatives, polyvinyl acetates, polyvinylalcohols, proteinsor pectins, or yet the materials cited in reference texts such as H.Scherz, Hydrokolloids: Stabilisatoren, Dickungs- and Gehermittel inLebensmittel, Band 2 der Schriftenreihe Lebensmittelchemie,Lebensmittelqualität, Behr's VerlagGmbH & Co., Hamburg, 1996. Theencapsulation is a well known process to a person skilled in the art,and may be performed, for instance, using techniques such asspray-drying, agglomeration or yet extrusion; or consists of a coatingencapsulation, including coacervation and complex coacervationtechniques.

By “perfumery base” we mean here a composition comprising at least oneperfuming co-ingredient.

Said perfuming co-ingredient is not of the formula (I). Moreover, by“perfuming co-ingredient” it is meant here a compound, which is used inperfuming preparation or composition to impart a hedonic effect. Inother words such a co-ingredient, to be considered as being a perfumingone, must be recognized by a person skilled in the art as being able toimpart or modify in a positive or pleasant way the odor of acomposition, and not just as having an odor.

The nature and type of the perfuming co-ingredients present in the basedo not warrant a more detailed description here, which in any case wouldnot be exhaustive, the skilled person being able to select them on thebasis of its general knowledge and according to intended use orapplication and the desired organoleptic effect. In general terms, theseperfuming co-ingredients belong to chemical classes as varied asalcohols, lactones, aldehydes, ketones, esters, ethers, acetates,nitriles, terpenoids, nitrogenous or sulphurous heterocyclic compoundsand essential oils, and said perfuming co-ingredients can be of naturalor synthetic origin. Many of these co-ingredients are in any case listedin reference texts such as the book by S. Arctander, Perfume and FlavorChemicals, 1969, Montclair, N.J., USA, or its more recent versions, orin other works of a similar nature, as well as in the abundant patentliterature in the field of perfumery. It is also understood that saidco-ingredients may also be compounds known to release in a controlledmanner various types of perfuming compounds.

For the compositions which comprise both a perfumery carrier and aperfumery base, other suitable perfumery carriers, than those previouslyspecified, can be also ethanol, water/ethanol mixtures, limonene orother terpenes, isoparaffins such as those known under the trademarkIsopar® (origin: Exxon Chemical) or glycol ethers and glycol etheresters such as those known under the trademark Dowanol® (origin: DowChemical Company).

By “perfumery adjuvant” we mean here an ingredient capable of impartingadditional added benefit such as a color, a particular light resistance,chemical stability, etc. A detailed description of the nature and typeof adjuvant commonly used in perfuming bases cannot be exhaustive, butit has to be mentioned that said ingredients are well known to a personskilled in the art.

An invention's composition consisting of at least one compound offormula (I) and at least one perfumery carrier represents a particularembodiment of the invention as well as a perfuming compositioncomprising at least one compound of formula (I), at least one perfumerycarrier, at least one perfumery base, and optionally at least oneperfumery adjuvant.

It is useful to mention here that the possibility to have, in thecompositions mentioned above, more than one compound of formula (I) isimportant as it enables the perfumer to prepare accords, perfumes,possessing the odor tonality of various compounds of the invention,creating thus new tools for their work.

Preferably, any mixture resulting directly from a chemical synthesis,e.g. without an adequate purification, in which the compound of theinvention would be involved as a starting, intermediate or end-product,could not be considered as a perfuming composition according to theinvention.

Furthermore, the invention's compound can also be advantageously used inall the fields of modern perfumery to positively impart or modify theodor of a consumer product into which said compound (I) is added.Consequently, a perfumed article comprising:

-   i) as perfuming ingredient, at least one compound of formula (I), as    defined above, or an invention's perfuming composition; and-   ii) a consumer product base;    is also an object of the present invention.

For the sake of clarity, it has to be mentioned that, by “consumerproduct base” we mean here a consumer product, which is compatible withperfuming ingredients. In other words, a perfumed article according tothe invention comprises the functional formulation, as well asoptionally additional benefit agents, corresponding to a consumerproduct, e.g. a detergent or an air freshener, and an olfactiveeffective amount of at least one invention's compound.

The nature and type of the constituents of the consumer product do notwarrant a more detailed description here, which in any case would not beexhaustive, the skilled person being able to select them on the basis ofits general knowledge and according to the nature and the desired effectof said product.

Examples of suitable consumer product bases include solid or liquiddetergents and fabric softeners as well as all the other articles commonin perfumery, namely perfumes, colognes or after-shave lotions, perfumedsoaps, shower or bath salts, mousses, oils or gels, hygiene products orhair care products such as shampoos, body-care products, deodorants orantiperspirants, air fresheners and also cosmetic preparations. Asdetergents there are intended applications such as detergentcompositions or cleaning products for washing up or for cleaning varioussurfaces, e.g. intended for textile, dish or hard-surface treatment,whether they are intended for domestic or industrial use. Other perfumedarticles are fabric softeners, fabric refreshers, ironing waters,papers, wipes or bleaches.

Some of the above-mentioned consumer product bases may represent anaggressive medium for the invention's compound, so that it may benecessary to protect the latter from premature decomposition, forexample by encapsulation.

The proportions in which the compounds according to the invention can beincorporated into the various aforementioned articles or compositionsvary within a wide range of values. These values are dependent on thenature of the article to be perfumed and on the desired organolepticeffect as well as the nature of the co-ingredients in a given base whenthe compounds according to the invention are mixed with perfumingco-ingredients, solvents or additives commonly used in the art.

For example, in the case of perfuming compositions, typicalconcentrations are in the order of 0.001% to 10% by weight, or evenmore, of the compounds of the invention based on the weight of thecomposition into which they are incorporated. Concentrations lower thanthese, such as in the order of 0.01% to 1% by weight, can be used whenthese compounds are incorporated into perfumed articles, percentagebeing relative to the weight of the article.

The invention's compounds can be prepared according to a methodcomprising the preparation of an ester of the invention, which can beconverted into an alcohol by reduction, and finally the oxidation ofsaid alcohol into an invention's aldehyde. The alcohol and the aldehydecan be subsequently be transformed into an ether, acetal or cyanideaccording to the invention using standard methods known from the art.The ester itself can be prepared by reacting an appropriate orthoesterwith an appropriate allyl-benzyl alcohol, under Claisen rearrangementconditions, as show in the scheme herein below:

Using such methodology, the alcohols and esters according to theinvention are also valuable intermediates for the production of thealdehydes and cyanides of formula (I).

Alternatively, the invention's compounds can be obtained by a processcomprising the following key steps:

The aldehyde can be then transformed into the desired invention'scompound using standard methods.

Other methods for the production of the aldehydes (I) are also possible,as described in the Examples.

Examples of all said methodologies are provided herein below in theExamples.

EXAMPLES

The invention will now be described in further detail by way of thefollowing examples, wherein the abbreviations have the usual meaning inthe art, the temperatures are indicated in degrees centigrade (° C.);the NMR spectral data were recorded in CDCl₃ (if not stated otherwise)with a 360 or 400 MHz machine for ¹H and ¹³C, the chemical shifts δ areindicated in ppm with respect to TMS as standard, the coupling constantsJ are expressed in Hz.

Example 1 Synthesis of Compounds of Formula (I) Methyl(4E)-4-methyl-5-(4-methylphenyl)-4-pentenoate

Trimethyl orthoacetate (273 g, 2.24 mol) and1-(4-methylphenyl)-2-methyl-2-propen-1-ol (91.4% pure, 39.92 g, 0.224mol) were heated in the presence of propionic acid (0.5 ml) in an oilbath at 120°-150° C. The methanol formed during the reaction wasdistilled first, followed by the excess orthoacetate. The product wasthen freed from residual orthoacetate under vacuum and purified bycolumn chromatography on silica gel (eluent: heptanes/ethyl acetate 25:1to 5:1), followed by bulb-to-bulb distillation (100° C./0.001 mbar).19.62 g (yield=40%) of the desired product were obtained.

¹³C-NMR: 173.66 (s), 136.24 (s), 135.68 (s), 135.25 (s), 128.76 (d),128.73 (d), 125.75 (d), 51.56 (q), 35.67 (t), 33.00 (t), 21.11 (q),17.64 (q).

¹H-NMR: 7.10 (s, 4H), 6.25 (s, 1H), 3.68 (s, 3H), 2.55-2.45 (m, 4H),2.32 (s, 3H), 1.87 (s, 3H).

(4E)-4-Methyl-5-(4-methylphenyl)-4-penten-1-ol

A solution of methyl (4E)-4-methyl-5-(4-methylphenyl)-4-pentenoate(17.18 g, 0.079 mol) in dry THF (300 ml) was treated, at −78° C. undernitrogen, with solid lithium aluminum hydride (3.15 g, 0.079 mol) in oneportion. After 5 minutes the cooling bath was removed and the reactionallowed to reach room temperature and then cooled to 0° C. and treatedsuccessively with water (3.15 ml), 5% aqueous sodium hydroxide (9.45 ml)and water (3.15 ml). The reaction was stirred at room temperature for 30minutes. Anhydrous solid sodium sulfate was added (10 g) and stirringcontinued for 5 minutes. The solid was filtered off, rinsed with diethylether and solvents were removed under vacuum. The product was purifiedby column chromatography on silica gel (eluent: heptanes/ethyl acetate5:1 to 1:1) followed by bulb-to-bulb distillation (120° C./0.001 mbar).12.54 g (yield=66%) of the desired product were obtained.

¹³C-NMR: 137.75 (s), 135.50 (s), 135.48 (s), 128.74 (d), 128.69 (d),125.06 (d), 62.55 (t), 36.97 (t), 30.91 (t), 21.10 (q), 17.73 (q).

¹H-NMR: 7.12 (s, 4H), 6.25 (broad s, 1H), 3.65 (q, J=6, 2H), 2.32 (s,3H), 2.22 (t, J=7, 2H), 2.04 (t, J=6, 1H), 1.86 (s, 3H), 1.78 (m, 2H).

(4E)-4-methyl-5-(4-methylphenyl)-4-pentenal

Solid pyridinium chlorochromate (13.2 g, 0.06 mol) was added in oneportion to a pre-cooled (−10° C.) solution of(4E)-4-Methyl-5-(4-methylphenyl)-4-penten-1-ol (9.88 g, 0.052 mol) indry dichloromethane (250 ml) under nitrogen. After 30 minutes, thereaction was warmed up to room temperature. After 1 hour, diethyl ether(700 ml) was added to the reaction. After stirring for 10 minutes, thereaction was filtered through silica gel, rinsing with diethyl ether.The solvent was removed under vacuum and the residue was purified bycolumn chromatography on silica gel (eluent: heptanes/ethyl acetate10:1) followed by bulb-to-bulb distillation (100° C./0.001 mbar). 3.55 g(yield=36%) of the desired product were obtained.

¹³C-NMR: 202.10 (d), 135.96 (s), 135.78 (s), 135.06 (s), 128.78 (d),128.70 (d), 125.67 (d), 42.24 (t), 32.75 (t), 21.11 (q), 17.82 (q).

¹H-NMR: 9.80 (t, J=2.5, 1H), 7.12 (s, 4H), 6.35 (s, 1H), 2.62 (td,J_(d)=2.5, J_(r)=7, 2H), 2.49 (t, J=7, 2H), 2.32 (s, 3H), 1.86 (s, 3H).

Methyl (4E)-4-methyl-5-phenyl-4-pentenoate

Trimethyl orthoacetate (186 g, 1.52 mol) and1-phenyl-2-methyl-2-propen-1-ol (90% pure from Alfa Aesar, 25 g, 0.152mol) were heated in the presence of propionic acid (0.2 ml) in an oilbath at 145° C. for 4 hours. The methanol formed during the reaction wasdistilled. The excess orthoacetate was then removed under vacuum and theresidue was purified by column chromatography on silica gel (eluent:heptanes/ethyl acetate 25:1 to 8:1) followed by bulb-to-bulbdistillation (67° C./0.001 mbar). 6.5 g (yield=21%) of the desiredproduct were obtained.

¹³C-NMR: 173.61 (s), 138.15 (s), 136.99 (s), 128.82 (d), 128.05 (d),126.10 (d), 125.69 (d), 51.58 (q), 35.61 (t), 32.95 (t), 17.64 (q).

¹H-NMR: 7.33-7.28 (m, 2H), 7.25-7.15 (m, 3H), 6.29 (s, 1H), 3.69 (s,3H), 2.57-2.46 (m, 4H), 1.86 (s, 3H).

(4E)-4-methyl-5-phenyl-4-penten-1-ol

A solution of methyl (4E)-4-methyl-5-phenyl-4-pentenoate (3.5 g, 0.016mol) in dry THF (100 ml) was treated, at −78° C. under nitrogen, withsolid lithium aluminum hydride (1 g, 0.025 mol) in one portion. After 5minutes, the cooling bath was removed and the reaction allowed reachingroom temperature and then cooled to 0° C. and treated successively withwater (1 ml), 5% aqueous sodium hydroxide (3 ml) and water (1 ml). Thereaction was stirred at room temperature for 30 minutes. Anhydrous solidsodium sulfate was added (3 g) and stirring continued for 5 minutes. Thesolid was filtered off, rinsed with diethyl ether and the filtrate wasevaporated under vacuum. The product was purified by bulb-to-bulbdistillation (84° C./0.002 mbar). 2.88 g (yield=100%) of the desiredproduct were obtained.

¹³C-NMR: 138.49 (s), 138.40 (s), 128.79 (d), 128.17 (d), 125.92 (d),125.20 (d), 62.52 (t), 36.92 (t), 30.89 (t), 17.74 (q).

¹H-NMR: 7.32-7.27 (m, 2H), 7.25-7.14 (m, 3H), 6.29 (s, 1H), 3.67 (t,J=7, 2H), 2.24 (t, J=7, 2H), 2.05 (s, 1H), 1.86 (s, 3H), 1.78 (m, 2H).

(4E)-4-methyl-5-phenyl-4-pentenal

Solid pyridinium chlorochromate (4.21 g, 0.02 mol) was added in oneportion to a cooled (−10° C.) solution of(4E)-4-methyl-5-phenyl-4-penten-1-ol (2.25 g, 0.013 mol) in drydichloromethane (50 ml) under nitrogen. After 30 minutes, the reactionwas warmed up to room temperature. After 1 hour, diethyl ether (250 ml)was added to the reaction. After stirring for 10 minutes, the reactionwas filtered through silica gel and the solid rinsed with diethyl ether.The solvent was removed under vacuum and the residue was purified bycolumn chromatography on silica gel (eluent: heptanes/ethyl acetate25:1) followed by bulb-to-bulb distillation (82° C./0.002 mbar). 1.21 g(yield=53%) of the desired product was obtained.

¹³C-NMR: 201.98 (d), 137.97 (s), 136.71 (s), 128.80 (d), 128.08 (d),126.17 (d), 125.81 (d), 42.19 (t), 32.68 (t), 17.82 (q).

¹H-NMR: 9.70 (d, J=2.5, 1H), 7.32-7.27 (m, 2H), 7.24-7.17 (m, 3H), 6.29(s, 1H), 2.68-2.60 (m, 2H), 2.53-2.47 (m, 2H), 1.86 (s, 3H).

Ethyl (4E)-4-methyl-5-(4-methylphenyl)-4-pentenoate

1-(4-methylphenyl)-2-methyl-2-propen-1-ol (64.9 g, 0.4 mol) and triethylorthoacetate (335 g, 2 mol) were heated in the presence of propionicacid (0.5 ml) in an oil bath at 150° C. (the ethanol formed during thereaction distills during this period) for 3 hours, then progressively to200° C. (to distill off the excess orthoacetate). The product was thendistilled under high vacuum (105° C./0.001 mbar) through a 20-cm Widmercolumn. 21.5 g of the desired product were obtained (94% purity,yield=24%).

¹³C-NMR: 173.23 (s), 136.30 (s), 135.65 (s), 135.27 (s), 128.75 (d),128.72 (d), 125.5 (d), 60.34 (t), 35.31 (t), 33.23 (t), 21.11 (q), 17.65(q), 14.29 (q).

¹H-NMR: 7.10 (s, 4H), 6.25 (s, 1H), 3.63 (q, J=7, 2H), 2.50 (m, 4H),2.32 (s, 3H), 1.86 (s, 3H), 1.25 (t, J=7, 3H).

Ethyl (4E)-2,4-dimethyl-5-(4-methylphenyl)-4-pentenoate

n-Butyl lithium (1.6 M in hexanes from Fluka, 70 ml, 0.111 mol) wasadded rapidly to a solution of diisopropylamine (11.7 g, 0.116 mol) indry THF (200 ml) under nitrogen, maintaining the temperature below −20°C. by cooling in a dry ice-acetone bath. After cooling to −78° C., dryDMPU (14.9 g, 0.116 mol) was added drop-wise for 5 minutes. Then, ethyl(4E)-4-methyl-5-(4-methylphenyl)-4-pentenoate (21.5 g, 0.092 mol) wasadded in 10 minutes. The reaction was warmed up to 0° C. and kept for 20minutes at this temperature before cooling back to −78° C. Methyl iodide(66 g, 0.46 mol) was added drop-wise. The reaction was warmed up to roomtemperature and stirred overnight. It was then poured onto water andextracted twice with diethyl ether. Each organic fraction was washedwith water and brine. Combined extracts are dried over solid anhydroussodium sulfate. The solid was filtered off, rinsed with diethyl ether.Solvents are removed under vacuum and the product was purified bybulb-to-bulb distillation (125° C./0.04 mbar). 18.5 g of colorlessliquid were obtained (yield=81%).

¹³C-NMR: 176.40 (s), 135.67 (s), 135.28 (s), 135.17 (s), 128.78 (d),128.73 (d), 127.07 (d), 60.22 (t), 45.04 (t), 38.19 (d), 21.12 (q),17.53 (q), 16.75 (q), 14.30 (q).

¹H-NMR: 7.12 (s, 4H), 6.25 (s, 1H), 3.63 (q, J=7, 2H), 2.72 (m, 1H),2.53 (m, 1H), 2.32 (s, 3H), 2.21 (m, 1H), 1.83 (s, 3H), 1.23 (t, J=7,3H), 1.17 (d, J=7, 3H).

Methyl (4E)-2,4-dimethyl-5-(4-methylphenyl)-4-pentenoate

A solution of sodium hydroxide (7.8 g, 0.195 mol) in water (25 ml) wasadded to a solution of ethyl(4E)-2,4-dimethyl-5-(4-methylphenyl)-4-pentenoate (16 g, 0.065 mol) inethanol (70 ml) at room temperature. The reaction was stirred overnightbefore removing ethanol under vacuum. Water (200 ml) was added to theresidue which was washed twice with diethyl ether. Each organic phasewas treated with water. Combined aqueous phases were treated with 5%aqueous HCl (150 ml). The resulting solution was extracted twice withdiethyl ether. Each organic fraction was washed with water and brine,before being combined and dried over solid anhydrous sodium sulfate. Thesolid was filtered off, rinsed with diethyl ether. The solvent wasremoved to a obtain a crude carboxylic acid. The crude acid wasdissolved in absolute methanol (250 ml) under nitrogen. Acetyl chloride(11 g, 0.142 mol) was added drop-wise without external cooling(exothermic). After 4 hours, solvents were removed under vacuum and theproduct was directly chromatographed on silica gel (eluent:heptanes/ethyl acetate 25:1 to 5:1). Bulb-to-bulb distillation (123°C./0.065 mbar) gives the desired methyl ester (8.4 g, yield=56%).

¹³C-NMR: 176.86 (s), 135.72 (s), 135.25 (s), 135.10 (s), 128.75 (d),128.72 (d), 127.14 (d), 51.54 (q), 45.00 (t), 38.14 (d), 21.12 (q),17.49 (q), 16.67 (q).

¹H-NMR: 7.11 (s, 4H), 6.25 (s, 1H), 3.65 (s, 3H), 2.73 (m, 1H), 2.54 (m,1H), 2.32 (s, 3H), 2.23 (m, 1H), 1.82 (s, 3H), 1.18 (d, J=7 Hz, 3H).

1-[1-(Allyloxy)-2-methyl-2-propenyl]-4-methylbenzene

Solid sodium tert-butylate (66.65 g, 0.589 mol) was dissolved undernitrogen in dry THF (350 ml) and1-(4-methylphenyl)-2-methyl-2-propen-1-ol (41.16 g, 0.239 mol) in dryTHF (25 ml) was added in 15 minutes without external cooling. Thereaction was further stirred at room temperature for 50 minutes. Tetrabutyl ammonium iodide (5.04 g, 0.014 mol) was added followed by allylchloride (40 g, 0.518 mol) in 25 minutes (exothermic to 47° C.). Thereaction was stirred for 24 hours, before adding more tetra butylammonium iodide (2.30 g, 0.006 mol) and allyl chloride (9.30 g, 0.120mol). After stirring for 24 hours at room temperature, the reaction waspoured onto ice, diluted with MTBE and acidified with aqueous phosphoricacid. The organic phase was washed with brine, saturated aqueous sodiumbicarbonate and brine and dried over solid anhydrous sodium sulfate. Thesolid was filtered off, rinsed with MTBE and solvents were removed undervacuum. The product was purified by distillation through a 35-cm Fishercolumn. 38.78 g of the desired allyl ether were obtained (yield=80%).B.P.=79° C./1.6 mbar

¹³C-NMR: 145.26 (s), 137.57 (s), 136.91 (s), 135.00 (d), 128.84 (d),126.61 (d), 116.44 (t), 112.58 (t), 84.20 (d), 69.13 (t), 21.12 (q),17.74 (q).

¹H-NMR: 7.18 (m, 4H), 5.98-5.88 (m, 1H), 5.30 (m, 1H), 5.15 (m, 1H),5.12 (m, 1H), 4.94 (m, 1H), 4.72 (s, 1H), 4.02-3.90 (m, 2H), 2.32 (s,3H), 1.58 (s, 3H).

(4E)-2,4-dimethyl-5-(4-methylphenyl)-4-pentenal

The 1-[1-(allyloxy)-2-methyl-2-propenyl]-4-methylbenzene (24 g, 0.116mol) and [RuCl₂(PPh₃)₃] (200 mg) were heated in the presence of BHT (50mg) in pseudo-cumene (50 ml) at 170-180° C. (reflux) for 4 hours.

After cooling to room temperature, the solvent was removed under vacuumand the residue purified by column chromatography on silica gel (eluent:heptanes/ethyl acetate 25:1) followed by fractional distillation using a20-cm Widmer column. 5 g of the desired aldehyde were obtained(yield=21%). P.P.=73° C./0.12 mbar

¹³C-NMR: 204.73 (d), 135.86 (s), 135.00 (s), 134.38 (s), 128.79 (d),128.72 (d), 127.57 (d), 44.59 (d), 41.70 (t), 21.11 (q), 17.66 (q),13.16 (q).

¹H-NMR: 9.68 (d, J=2.5, 1H), 7.12 (s, 4H), 6.27 (s, 1H), 2.67-2.57 (m,2H), 2.32 (s, 3H), 2.14 (m, 1H), 1.85 (s, 3H), 1.11 (d, J=7, 3H).

1-[1-(2-Butenyloxy)-2-methyl-2-propenyl]-4-methylbenzene

Solid potassium tert-butylate (47 g, 0.411 mol) was added portion-wise(ca 15 min) to a solution of 1-(4-methylphenyl)-2-methyl-2-propen-1-ol(96% pure, 46.27 g, 0.274 mol) in dry THF (500 ml) at room temperatureunder nitrogen (exothermic to 30° C.). After 1 more hour at roomtemperature, the reaction was cooled to 5° C. and tetra butyl ammoniumiodide (5.2 g, 0.014 mol) was added followed by crotyl chloride (74.4 g,0.822 mol) drop-wise. The reaction was warmed up to room temperatureovernight and poured onto water (800 ml). The reaction was extractedtwice with ethyl acetate. Each organic phase was washed with water andbrine. Combined extracts were dried over solid anhydrous sodium sulfate.The solid was filtered off, rinsed with diethyl ether and the solventswere removed under vacuum. The product was purified by distillationunder vacuum through a 20-cm Widmer column A 3:1 mixture of E/Z isomerswas obtained (96% pure, 57.58 g, yield=93%). B.P.=74° C./0.005 mbar

¹³C-NMR (E-isomer): 145.38 (s), 137.73 (s), 136.82 (s), 128.81 (d),127.84 (d), 127.51 (d), 126.65 (d), 112.52 (t), 84.01 (d), 68.97 (t),21.11 (q), 17.80 (q), 13.23 (q).

¹H-NMR: 7.18 (m, 4H), 5.72-5.55 (m, 2H), 5.10 (s, 1H), 4.92 (m, 1H),4.70 (s, 1H), 4.08-3.80 (m, 2H), 2.32 (s, 3H), 1.70 (m, 3H), 1.55 (s,3H).

2-Ethyl-4-methyl-5-(4-methylphenyl)-4-pentenal

The 1-[1-(2-butenyloxy)-2-methyl-2-propenyl]-4-methylbenzene (50.12 g,0.232 mol), [RuCl₂(PPh₃)₃] (400 mg), BHT (50 mg) and pseudo-cumene (60ml) were heated together in an autoclave placed in an oil bath at 180°C. for 5 hours. After cooling to room temperature, the pseudo-cumene wasdistilled off (40° C./5 mbar) and the residue chromatographed on silicagel (eluent: heptanes/ethyl acetate 50:1 to 25:1), then distilled undervacuum through a 20-cm Widmer column. 18.1 g of the desired product wereobtained (yield=36%). B.P.=80° C./0.001 mbar

¹³C-NMR: 204.97 (d), 135.84 (s), 135.01 (s), 134.62 (s), 128.90 (d),128.78 (d), 127.36 (d), 51.51 (d), 39.91 (t), 21.82 (t), 21.11 (q),17.82 (q), 11.47 (q).

¹H-NMR: 9.62 (d, J=2.5, 1H), 7.12 (s, 4H), 6.27 (s, 1H), 2.55-2.37 (m,2H), 2.32 (s, 3H), 2.25 (m, 1H), 1.80 (s, 3H), 1.72-1.40 (m, 2H), 0.95(t, J=7, 3H).

[1-(2-Butenyloxy)-2-methyl-2-propenyl]benzene

Solid potassium tert-butylate (26 g, 0.228 mol) was added portion-wise(ca 15 min) to a solution of 1-phenyl-2-methyl-2-propen-1-ol (90% purefrom Alfa Aesar, 25 g, 0.152 mol) in dry THF (300 ml) at roomtemperature under nitrogen (exothermic to 30° C.). After 1 more hour atroom temperature, the reaction was cooled to 5° C. and tetra butylammonium iodide (2.9 g, 0.08 mol) was added followed by crotyl chloride(41.3 g, 0.456 mol) drop-wise. The reaction was warmed up to roomtemperature overnight and poured onto water (500 ml). The reaction wasextracted twice with ethyl acetate. Each organic phase was washed withwater and brine. Combined extracts were dried over solid anhydroussodium sulfate. The solid was filtered off, rinsed with diethyl etherand the solvents were removed under vacuum. After column chromatographyon silica gel (eluent: heptanes/ethyl acetate 25:1) the product waspurified by bulb-to-bulb distillation (100° C./0.001 mbar). A 3:1mixture of E/Z isomers was obtained (95% pure, 26.78 g, yield=83%).

¹³C-NMR (E-isomer): 145.26 (s), 140.73 (s), 128.93 (d), 128.10 (d),127.76 (d), 127.16 (d), 126.67 (d), 112.86 (t), 84.14 (d), 69.01 (t),17.80 (q), 17.68 (q).

¹H-NMR: 7.37-7.20 (m, 5H), 5.75-5.55 (m, 2H), 5.12 (s, 1H), 4.95 (m,1H), 4.75 (s, 1 H), 4.10-3.80 (m, 2H), 1.70 (m, 3H), 1.62-1.55 (m, 3H).

2-Ethyl-4-methyl-5-phenyl-4-pentenal

The [1-(2-butenyloxy)-2-methyl-2-propenyl]benzene (26.9 g, 0.126 mol),[RuCl₂(PPh₃)₃] (280 mg), BHT (100 mg) and pseudo-cumene (25 ml) wereheated together in an autoclave placed in an oil bath at 180° C. for 4hours. After cooling to room temperature, the pseudo-cumene wasdistilled off (40° C./5 mbar) and the residue purified by columnchromatography on silica gel (eluent: heptanes/ethyl acetate 50:1 to10:1) followed by bulb-to-bulb distillation (87° C./0.008 mbar). 13.0 gof the desired product were obtained (yield=51%) as a 9:1 mixture of E/Zisomers.

¹³C-NMR (E isomer): 204.91 (d), 137.89 (s), 135.39 (s), 128.82 (d),128.07 (d), 127.47 (d), 126.22 (d), 51.47 (d), 39.83 (t), 21.82 (t),17.81 (q), 11.46 (q).

¹H-NMR: 9.62 (d, J=2.5, 1H), 7.32-7.27 (m, 2H), 7.23-7.13 (m, 3H), 6.30(s, 1H), 2.57-2.37 (m, 2H), 2.28 (m, 1H), 1.85 (s, 3H), 1.73-1.40 (m,2H), 0.95 (t, J=7, 3H).

(1E)-[3-(allyloxy)-2-methyl-1-propenyl]benzene

Solid potassium tert-butylate (110 g, 0.960 mol) was added portion-wise(1 hour) to a solution of trans-2-methyl-3-phenyl-2-propen-1-ol (100 g,0.950 mol) in dry THF (1 liter) at room temperature under nitrogen.After 1 more hour at room temperature, the reaction was cooled to 5° C.and tetra butyl ammonium iodide (12.1 g, 0.032 mol) was added followedby allyl chloride (100 g, 1.280 mol) drop-wise. The reaction was warmedup to room temperature overnight and poured onto water (2 liters). Thereaction was extracted twice with ethyl acetate. Each organic phase waswashed with water and brine. Combined extracts are dried over solidanhydrous sodium sulfate. The solid was filtered off, rinsed withdiethyl ether and the solvents were removed under vacuum. The productwas purified by distillation through a 20-cm Widmer column. 120.5 g ofthe desired compound was obtained (97% pure, 0.620 mol, 97%). B.P.=70°C./0.067 mbar

¹³C-NMR: 137.56 (s), 135.14 (s), 134.86 (d), 128.90 (d), 128.09 (d),126.84 (d), 126.42 (d), 116.93 (t), 76.21 (t), 70.84 (t), 15.47 (q).

¹H-NMR: 7.32-7.15 (m, 5H), 6.52 (s, 1H), 6.02-5.90 (m, 1H), 5.30 (m,1H), 5.20 (m, 1H), 4.02-3.98 (m, 4H), 1.89 (s, 3H).

(4E)-2,4-dimethyl-5-phenyl-4-pentenal

The (1E)-[3-(allyloxy)-2-methyl-1-propenyl]benzene (107.79 g, 0.571mol), [RuCl₂(PPh₃)₃] (3.13 g), BHT (1 g) and benzene (500 ml) wereheated together in an autoclave in an oil bath at 190° C. for 4 hours.After cooling to room temperature, solvents were evaporated and theproduct purified by column chromatography on silica gel (eluent:heptanes/ethyl acetate 10:1) followed by bulb-to-bulb distillation (88°C./0.009 mbar) to give 11.21 g of the desired compound (0.060 mol, 10%).

¹³C-NMR: 204.65 (d), 137.90 (s), 135.16 (s), 128.82 (d), 128.09 (d),127.68 (d), 126.25 (d), 44.56 (d), 41.63 (t), 17.66 (q), 13.18 (q).

¹H-NMR: 9.67 (d, J=2.5, 1H), 7.32-7.26 (m, 2H), 7.23-7.15 (m, 3H), 6.32(s, 1H), 2.66-2.58 (m, 2H), 2.18-2.10 (m, 1H), 1.83 (s, 3H), 1.10 (d,J=7, 3H).

2-Methyl-1-(3-methylphenyl)-2-propen-1-ol

3-Methylbenzaldehyde (Aldrich 97%, 62 g, 0.5 mol) was added drop-wiseover 1 hour to a commercial solution of 2-propenyl magnesium bromide inTHF (Aldrich 0.5 N, 800 ml, 0.4 mol), at −78° C. under nitrogen. Thecooling bath was removed and the reaction stirred for 5 hours, beforebeing cooled to 0° C. A saturated aqueous solution of ammonium chloride(300 ml) was added drop-wise at such a rate that the temperature waskept below 20° C. Diethyl ether (600 ml) was then added and the reactionwas transferred to a separating funnel. After shaking vigorously, thephases were separated. The organic phase was washed with water andsaturated aqueous sodium bicarbonate. Each aqueous phase wasre-extracted with diethyl ether. The organic fractions were combined anddried over solid anhydrous sodium sulfate. The solid was filtered off,rinsed with diethyl ether and the solvents were removed under vacuum.The product was purified by column chromatography on silica gel (eluent:heptanes/ethyl acetate 5:1) followed by distillation through a 20-cmWidmer column. 33 g of the desired product were obtained (yield=51%).B.P.=55° C./0.009 mbar

¹³C-NMR: 146.89 (s), 141.99 (s), 137.99 (s), 128.38 (d), 128.26 (d),127.13 (d), 123.59 (d), 110.98 (t), 77.83 (d), 21.42 (q), 18.32 (q).

¹H-NMR: 7.23-7.05 (m, 4H), 5.18 (s, 1H), 5.03 (s, 1H), 4.92 (s, 1H),2.32 (s, 3H), 2.20 (broad s, 1H), 1.47 (s, 3H).

(4E)-4-methyl-5-(3-methylphenyl)-4-pentenal

The 2-methyl-1-(3-methylphenyl-2-propen-1-ol (17.74 g, 0.109 mol),tri(ethylene glycol) divinyl ether (Aldrich 98%, 22.5 g, 0.109 mol) andmercury(II) acetate (1.05 g, 0.003 mol) were heated together undernitrogen at 155-160° C. (bath temperature) for 16 h. After cooling toroom temperature, the reaction was diluted with heptanes, washed withwater (3 times). Each aqueous phase was re-extracted with heptanes.Combined extracts were dried over solid anhydrous sodium sulfate. Thesolid was filtered off, rinsed with heptanes and the solvent was removedunder vacuum. The crude product was distilled using a Kügelrohr (140°C./0.001 mbar). The distillate was purified by column chromatography onsilica gel (eluent: heptanes/ethyl acetate (10:1 to 5:1) followed bybulb-to-bulb distillation (71° C./0.002 mbar). 5.41 g of the desiredproduct were obtained (yield=26%) as an 85:15 mixture of E/Z isomers.

¹³C-NMR (E isomer): 201.95 (d), 137.93 (s), 137.57 (s), 136.50 (s),129.57 (d), 127.98 (d), 127.06 (d), 125.92 (d), 125.86 (d), 42.26 (t),32.72 (t), 21.42 (q), 17.84 (q).

¹H-NMR (E isomer): 9.81 (t, J=2.5, 1H), 7.22-7.17 (m, 1H), 7.03-6.92 (m,3H), 6.25 (s, 1H), 2.65-2.46 (m, 4H), 2.32 (s, 3H), 1.85 (s, 3H).

ethyl (4E)-5-(4-methylphenyl)-4-hexenoate

Prepared as described for ethyl(4E)-4-methyl-5-(4-methylphenyl)-4-pentenoate using the followingreagents:

-   -   2-(4-methyl-1-phenyl)-3-buten-2-ol (0.093 mol)    -   Triethylorthoacetate (154 g; 0.93 mol)    -   Propionic acid (0.5 ml).

The product was purified by column chromatography on silica gel (elutingwith heptane/ethyl acetate 5:1) followed by bulb-to-bulb distillation.4.4 g of product were obtained (0.019 mol, 20%).

B.p.=100° C./0.001 mbar

13C-NMR: 173.19 (s); 140.79 (s); 136.37 (s); 135.96 (s); 128.86 (d);125.55 (d); 125.26 (d); 60.32 (t); 34.28 (t); 24.34 (t); 21.00 (q);15.83 (q); 14.27 (q)

1H-NMR: 7.20 (m, 4H); 5.68 (m, 1H); 4.12 (q, J=7 Hz, 2H); 2.55-2.40 (m,4H); 2.32 (s, 3H); 2.05 (s, 3H); 1.22 (t, J=7 Hz, 3H)

(4E)-5-(4-methylphenyl)-4-hexen-1-ol

Prepared as described for (4E)-4-methyl-5-(4-methylphenyl)-4-penten-1-olusing the following reagents:

-   -   ethyl (4E)-5-(4-methylphenyl)-4-hexenoate: 4.4 g (0.019 mol)    -   Lithium aluminium hydride: 95% pure; 1.2 g (0.03 mol)

The product was purified by bulb-to-bulb distillation. 3.4 g of desiredalcohol were obtained (0.017 mol; 89% yield).

B.p.=140° C./0.001 mbar

¹³C-NMR: 140.95 (s); 136.22 (s); 135.17 (s); 128.96 (d); 128.86 (d);126.77 (d); 125.64 (d); 125.47 (d); 62.53 (t); 32.59 (t); 25.06 (t);20.99 (q); 15.78 (q)

¹H-NMR: 7.20 (m, 4H); 5.72 (m, 1H); 3.65 (t, J=7 Hz, 2H); 2.32 (s, 3H);2.27 (q, J=7 Hz, 2H); 2.02 (s, 3H); 1.83 (broad s, 1H); 1.70 (t, J=7 Hz,2H)

(4E)-5-(4-methylphenyl)-4-hexenal

Prepared as described for (4E)-4-methyl-5-(4-methylphenyl)-4-pentenalusing the following reagents:

-   -   (4E)-5-(4-methylphenyl)-4-hexen-1-ol: 2.13 g (0.011 mol)    -   PCC: 5.8 g (0.022 mol)    -   Sodium acetate: 2 g

The product was purified by column chromatography on silica gel (elutingwith heptane/ethyl acetate 5:1) followed by bulb-to-bulb distillation.1.4 g of the desired aldehyde was obtained (0.0075 mol; 67% yield).

B.p.=100-120° C./0.001 mbar

¹³C-NMR: 202.05 (s); 140.58 (s); 136.50 (s); 136.17 (s); 128.90 (d);125.51 (d); 124.88 (d); 43.73 (t); 21.54 (t); 21.00 (q); 15.88 (q)

¹H-NMR: 9.80 (m, 1H); 7.18 (m, 4H); 5.68 (m, 1H); 2.60-2.48 (m, 4H);2.32 (s, 3H); 2.02 (s, 3H)

3-methyl-2-(4-methylphenyl)-3-buten-2-ol

Prepared as described for 2-methyl-1-(3-methylphenyl)-2-propen-1-olusing the following reagents:

-   -   p-methylacetophenone 70.6 g (0.5 mol)    -   isopropenyl magnesium bromide (0.5 N in THF; 800 ml; 0.4 mol).

The product was purified by column chromatography on silica gel(heptane/ethyl acetate 10:1 to 5:1) followed by bulb-to-bulbdistillation. 20.2 g of desired product were obtained (94% pure; 0.108mol; 27% yield).

B.p.=81° C./0.001 mbar

¹³C-NMR: 150.30 (s); 143.06 (s); 136.42 (s); 128.81 (d); 125.19 (d);110.42 (t); 76.75 (s); 28.56 (q); 20.98 (q); 19.13 (q)

¹H-NMR: 7.22 (m, 4H); 5.18 (m, 1H); 4.92 (m, 1H); 2.32 (s, 3H); 2.00 (s,1H); 1.66 (s, 3H); 1.60 (s, 3H)

(Z)-4-methyl-5-p-tolylhex-4-enal

Prepared as described for (4E)-4-methyl-5-(3-methylphenyl)-4-pentenalusing the following reagents:

-   -   3-methyl-2-(4-methylphenyl)-3-buten-2-ol: 19 g, 0.108 mol)    -   Tri(ethyleneglycol)divinyl ether (22.2 g; 0.108 mol)    -   Hg(II) acetate (1.05 g; 0.0032 mol)

The product was purified by column chromatography on silica gel (elutingwith heptane/ethyl acetate 10:1 to 2:1), followed by bulb-to-bulbdistillation. 2.4 g of the desired product were obtained as a 79:17mixture of Z/E isomers (97% chemically pure; 0.012 mol; 11% yield).

B.p.=85° C./0.001 mbar

¹³C-NMR (data for the major isomer): 202.57 (s); 141.77 (s); 135.64 (s);132.68 (s); 128.98 (d); 128.75 (s); 127.86 (d); 42.77 (t); 27.99 (t);21.40 (q); 21.08 (q); 17.67 (q)

¹H-NMR (data for the major isomer): 9.57 (t, J=2.5 Hz, 1H); 7.04 (m,4H); 2.40 (m, 2H); 2.32 (m, 3H); 2.25 (m, 2H); 1.92 (s, 3H); 1.76 (s,3H)

4-methyl-5-phenyl-4-hexenal

Prepared as described for (Z)-4-methyl-5-p-tolylhex-4-enal using thefollowing reagents:

-   -   3-Methyl-2-phenyl-but-3-en-2-ol (J. A. Marco et al., Tetrahedron        2003, 59, 4085) (9 g, 0.055 mol)    -   Tri(ethyleneglycol)divinyl ether (11.1 g; 0.055 mol)    -   Mercury(II) acetate (0.57 g; 0.00018 mol)

The product was purified by column chromatography on silica gel (elutingwith cyclohexane/ethyl acetate 19:1 to 9:1), followed by bulb-to-bulbdistillation 140-150° C. at 4.5 mbar. 0.70 g of the desired product wereobtained as a 38:62 mixture of Z/E isomers (95% chemically pure; 0.012mol; 7% yield).

¹³C-NMR: 202.6, 202.3 (s), 144.8, 144.7, 134.9, 133.7, 132.8 (s), 128.3,128.2, 128.1, 127.9, 126.2, 126.0 (d), 42.7, 42.4 (t), 27.9, 26.8 (t),21.4, 20.6, 19.6, 17.7 (q).

¹H-NMR: 9.85 (major, t, J=1.5, 1H), 9.57 (minor, t, J=2, 1H), 7.39-7.05(m, 5H), 2.64-2.58 (major, m, 2H), 2.55-2.49 (major, m, 2H), 2.43-2.37(minor, m, 2H), 2.25 (minor, t, J=7.4, 2H), 1.97 (major, bs, 3H), 1.93(minor, q, J=1.0, 3H), 1.78 (minor, q, J=1.0, 3H), 1.56 (major, q,J=1.1, 3H)

(E)-4-methyl-5-p-tolylpent-4-enenitrile

(4E)-4-methyl-5-(4-methylphenyl)-4-pentenal (3.2 g, 0.017 mol) andhydroxylamine hydrochloride (1.77 g, 0.025 mol) were heated together in95% ethyl alcohol (55 ml) at reflux for 4 hours. After cooling to roomtemperature, ethanol was removed on the rotavapor. The residue wasstirred in diethyl ether (250 ml) for 30 minutes. The solid was filteredoff, rinsed with diethyl ether and discarded. The filtrate wasevaporated under vacuum. The product was purified by columnchromatography on silica gel (eluent: heptane/ethyl acetate 11:1)followed by bulb-to-bulb distillation. 2.18 g of the desired compoundwere obtained (0.012 mol, 70% yield).

B.p.=80° C./0.001 mbar

¹³C-NMR: 136.19 (s); 134.57 (s); 133.75 (s); 128.85 (d); 128.77 (d);127.49 (d); 119.28 (s); 35.89 (t); 21.12 (q); 17.33 (q); 16.36 (t)

¹H-NMR: 7.13 (s, 4H); 6.32 (b.s, 1H); 2.52-2.43 (m, 4H); 2.32 (s, 3H);1.86 (s, 3H)

(4Z)-4-methyl-5-(4-methylphenyl)-4-pentenal

This isomer was isolated from top fractions of the distillation of(4E)-4-methyl-5-(4-methylphenyl)-4-pentenal by preparative gas phasechromatography.

¹³C-NMR: 201.96 (d), 136.06 (s), 135.89 (s), 135.00 (s), 128.95 (d),128.37 (d), 126.94 (d), 42.25 (t), 24.94 (t), 23.67 (q), 21.10 (q).

¹H-NMR: 9.71 (s, 1H), 7.11 (d, J=7.8 Hz, 2H), 7.05 (d, J=7.8 Hz, 2H),6.31 (s, 1H), 2.55 (s, 4H), 2.32 (s, 3H), 1.85 (s, 3H).

Example 2 Preparation of a Perfuming Composition

An eau de cologne for man, of the musky-herbaceous type, was prepared byadmixing the following ingredients:

Ingredient Parts by weight Carbinol acetate 50 10* Cis-3-Hexenol acetate20 Citronellyl acetate 20 Linalyl acetate 350 10%* Isoeugenyl acetate 4016-Hexadecanolide 10 10%* Methyl anthranilate 40 Cetalox ®¹⁾ 10 10%*Cis-3-Hexenol 20 10%* Citral 30 Coumarine 10 10%* Damascone Alpha 20Dihydromyrcenol 400 10%* Damascone Beta 20 Floralozone²⁾ 25 70%**Galaxolide ®³⁾ 600 Geranium essential oil 5 Hedione ®⁴⁾ HC 160Helvetolide ®⁵⁾ 80 Iso E Super ®⁶⁾ 200 Lavender essential oil 50Lilial ®⁷⁾ 200 10%* Methylnaphthylcetone 20 Mousse Cristal 40Romandolide ®⁸⁾ 500 Amyl salicylate 60 Benzyl salicylate 100Cis-3-Hexenol salicylate 200 Tonalide ®⁹⁾ 200 10%*2,4-Dimethyl-3-cyclohexene-1-carbaldehyde 20 3500 *in dipropyleneglycol**in isopropyle myristate ¹⁾8,12-epoxy-13,14,15,16-tetranorlabdane;origin: Firmenich SA, Geneva, Switzerland²⁾3-(4/2-ethylphenyl)-2,2-dimethylpropanal; origin: InternationalFlavors & Fragrances, USA³⁾1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-g-2-benzopyrane;origin: International Flavors & Fragrances, USA ⁴⁾methylcis-dihydrojasmonate; origin: Firmenich SA, Geneva, Switzerland⁵⁾(1S,1′R)-2-[1-(3′,3′-dimethyl-1′-cyclohexyl)ethoxy]-2-methylpropylpropanoate; origin: Firmenich SA, Geneva, Switzerland⁶⁾1-(octahydro-2,3,8,8-tetramethyl-2-naphtalenyl)-1-ethanone; origin:International Flavors & Fragrances, USA⁷⁾3-(4-tert-butylphenyl)-2-methylpropanal; origin: Givaudan SA, Geneva,Switzerland⁸⁾(1S,1′R)-[1-(3′,3′-dimethyl-1′-cyclohexyl)ethoxycarbonyl]methylpropanoate; origin: Firmenich SA, Geneva, Switzerland⁹⁾(5,6,7,8-tetrahydro-3,5,5,6,8,8-hexamethyl-2-naphtyl)-1-ethanone;origin: Givaudan SA, Geneva, Switzerland

When there were added 200 parts by weight of(4E)-4-methyl-5-(4-methylphenyl)-4-pentenal to the above-described eaude cologne, then the new fragrance acquired a body and apowdery-mimosa/lily of the valley sweetness which is very cosmetic, itbrings to the eau de cologne also a nursing aspect.

When instead of the above invention's compound there was added the sameamount of (4E)-2,4-dimethyl-5-(4-methylphenyl)-4-pentenal, then the newfragrance became more green, more anisic.

The addition to the original eau de cologne of the same amount ofMefranal® provided a new fragrance which acquired a clear citrus,citronella character.

Example 3 Preparation of a Perfuming Composition

A cologne, of the floral-watery type, was prepared by admixing thefollowing ingredients:

Ingredient Parts by weight 10%* Phenylacetic aldehyde 2016-Hexadecanolide 40 Dihydro Beta Ionone 3507-Methyl-2H,4H-1,5-benzodioxepin-3-one 80 Citronellol 300 Allyl(cyclohexyloxy)-acetate 20 Decal 20 Dimetol ®¹⁾ 20 10%* Ethylvanilline100 Eugenol 80 Exaltolide ®²⁾ 360 70%** Galaxolide ®³⁾ 2200 Hedione ®⁴⁾1000 10%* Indol 150 Beta Ionone 20 Iso E Super ®⁵⁾ 1300 Lilial ®⁶⁾ 1150Linalool 270 Lyral ®⁷⁾ 250 10%* 2,6-Dimethyl-5-heptanal 50Paradisone ®⁸⁾ 100 Phenethylol 70 10%*2,4-Dimethyl-3-cyclohexene-1-carbaldehyde 50 8000 *in dipropyleneglycol**in isopropyle myristate ¹⁾2,6-dimethyl-2-heptanol; origin: GivaudanSA, Geneva, Switzerland ²⁾pentadecanolide; origin: Firmenich SA, Geneva,Switzerland³⁾1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-g-2-benzopyrane;origin: International Flavors & Fragrances, USA ⁴⁾methyldihydrojasmonate; origin: Firmenich SA, Geneva, Switzerland⁵⁾1-(octahydro-2,3,8,8-tetramethyl-2-naphtalenyl)-1-ethanone; origin:International Flavors & Fragrances, USA⁶⁾3-(4-tert-butylphenyl)-2-methylpropanal; origin: Givaudan SA, Geneva,Switzerland⁷⁾4/3-(4-hydroxy-4-methylpentyl)-3-cyclohexene-1-carbaldehyde; origin:International Flavors & Fragrances, USA ⁸⁾(+)-methyl(1R)-cis-3-oxo-2-pentyl-1-cyclopentaneacetate; origin: Givaudan SA,Geneva, Switzerland

When there were added 300 parts by weight of(4E)-4-methyl-5-(4-methylphenyl)-4-pentenal to the above-described eaude cologne, then it was obtained a new cologne having a considerablyreinforced watery aspect going with a nice floral-lily of the valley andpowdery-mimosa note.

When instead of the above invention's compound there was added the sameamount of (4E)-2,4-dimethyl-5-(4-methylphenyl)-4-pentenal, then the newcologne, compared to the one obtained by the addition of(4E)-4-methyl-5-(4-methylphenyl)-4-pentenal, became more linden/verbenaand acquired also a slightly almond aspect.

The addition to the original eau de cologne of the same amount ofMefranal® provided a new fragrance which acquired a clear citrus,citronella character.

Example 4 Preparation of a Perfuming Composition

A perfuming composition for a fabric softener was prepared by admixingthe following ingredients:

Ingredient Parts by weight Benzyl acetate 150 Carbinol acetate 50 Anisicaldehyde 80 10%* C 12 Aldehyde 40 10%* C 8 Aldehyde 20 Hexylcinnamicaldehyde 150 10%* MNA Aldehyde 30 Methyl anthranilate 40 10%* Ethyl2-methylpentanoate 40 Undecalactone Gamma 50 Benzophenone 10 Cetalox ®¹⁾40 Lemon essential oil 50 Citronellol 1504-Cyclohexyl-2-methyl-2-butanol 220 Verdyl propionate 100 Coumarine 1503-(4-Isopropylphenyl)-2-methylpropanal 20 Damascone Alpha 10(1′R,E)-2-Ethyl-4-(2′,2′,3′-trimethyl-3′- 50cyclopenten-1′-yl)-2-buten-1-ol²⁾ Dihydromyrcenol 120 Ethylvanilline 20Habanolide ®³⁾ 100 Heliotropine 50 Iralia ®⁴⁾ Total 120 Lilial ®⁵⁾ 200Isopropyl methylbutyrate 10 Methylnaphthylketone 30 10%* Mousse Cristal60 Muscenone 6⁵⁾ Delta 20 Hedione ®⁷⁾ 250 10%* Neobutenone ®⁸⁾ Alpha 10Nirvanol ®⁹⁾ 30 Patchouli essential oil 20 Peonile ®¹⁰⁾ 200 Phenethylol250 Phenylhexanol 450 Orange essential oil 50 Hexyle salicylate 50Benzyl salicylate 200 Terpineol 50 Tetralinol 200 Undecavertol 20 YaraYara 20 2,4-Dimethyl-3-cyclohexene-1-carbaldehyde 20 4000 *indipropyleneglycol ¹⁾8,12-epoxy-13,14,15,16-tetranorlabdane; origin:Firmenich SA, Geneva, Switzerland ²⁾origin: Firmenich SA, Geneva,Switzerland ³⁾pentadecanolide; origin: Firmenich SA, Geneva, Switzerland⁴⁾mixture of methyl ionones; origin: Firmenich SA, Switzerland⁵⁾3-(4-tert-butylphenyl)-2-methylpropanal; origin: Givaudan-Roure SA,Vernier, Switzerland ⁶⁾3-methyl-(4)-cyclopentadecenone; origin:Firmenich SA, Switzerland ⁷⁾methyl dihydrojasmonate; origin: FirmenichSA, Switzerland ⁸⁾1-(5,5-dimethyl-1-cyclohexen-1-yl)-4-penten-1-one;origin: Firmenich SA, Switzerland⁹⁾3,3-dimethyl-5-(2,2,3-trimethyl-3-cyclopenten-1-yl)-4-penten-2-ol;origin: Firmenich SA, Switzerland¹⁰⁾cyclohexylidene(phenyl)acetonitrile; origin: Givaudan-Roure SA,Vernier, Switzerland

When there were added 100 parts by weight of(4E)-4-methyl-5-(4-methylphenyl)-4-pentenal to the above-describedperfume, then the new fragrance acquired spectacular character due to afloral sweetness, as well as a watery and powdery aspect. The effect wasclearly perceivable on a wet or dry fabric washed treated with asoftener containing said fragrance. The effect provided by theinvention's compound was much less chemical than the one obtained withanisic aldehyde, and was much more sweet-floral than the one obtained byusing the known ingredients 3-(4-methoxyphenyl)-2-methylpropanal or3-(1,3-benzodioxol-5-yl)-2-methylpropanal.

When instead of the above invention's compound there was added the sameamount of (4E)-2,4-dimethyl-5-(4-methylphenyl)-4-pentenal, then the newfragrance, compared to the one obtained by the addition of(4E)-4-methyl-5-(4-methylphenyl)-4-pentenal, became more aldehydic witha connotation of the anis-linden type.

The addition to the original eau de cologne of the same amount ofMefranal® provided a new fragrance which acquired a clear citrus,citronella character.

1.-10. (canceled)
 11. A method to confer, enhance, improve or modify theodor properties of a perfuming composition or of a perfumed article,which method comprises adding to the composition or article an effectiveamount of at least a compound of formula

wherein R is an ortho, meta or para substituent of the phenyl ring, andrepresents a hydrogen atom or a C₁₋₂ alkyl or alkoxyl group; R¹represents a hydrogen atom or a C₁₋₃ alkyl group; R² represents ahydrogen atom or a methyl or ethyl group; R³ represents a hydrogen atomor a methyl or ethyl group; and X represents a CHO, COOR⁴ or CN group,R⁴ being a methyl or ethyl group; and at least one of said R, R¹ or R²represents a group containing at least one carbon atom, and saidcompound being in the form of a E or Z isomer or of a mixture thereof.12. The method according to claim 11, wherein the compound is onewherein: R is an ortho, meta or para substituent of the phenyl ring andrepresents a hydrogen atom or a methyl or ethyl group; R¹ represents amethyl or ethyl group; R² represents a hydrogen atom or a methyl orethyl group; R³ represents a hydrogen atom or a methyl or ethyl group;and X represents a CHO, COOR⁴ or CN group, R⁴ being a methyl or ethylgroup.
 13. The method according to claim 11, wherein the compound is onewherein R, R² or R³ represents a hydrogen atom or methyl group, R¹represents a methyl group and X represents a CHO group.
 14. The methodaccording to claim 11, wherein the compound (I) is(4E)-4-methyl-5-(4-methylphenyl)-4-pentenal,(4E)-2,4-dimethyl-5-(4-methylphenyl)-4-pentenal,2,4-dimethyl-5-phenyl-4-pentenal, 4-methyl-5-phenyl-4-hexenal,4-methyl-5-phenyl-4-pentenal or Methyl(4E)-4-methyl-5-(4-methylphenyl)-4-pentenoate.
 15. A compound of formula

wherein R^(1′) represents a hydrogen atom or a methyl group; Yrepresents a CH₂OH group or a group X; R is an ortho, meta or parasubstituent of the phenyl, and represents a hydrogen atom or a C₁₋₂alkyl or alkoxyl group; R² represents a hydrogen atom or a methyl orethyl group; R³ represents a hydrogen atom or a methyl or ethyl group;and X represents a CHO, COOR⁴ or CN group, R⁴ being a methyl or ethylgroup; and the compound is in the form of a E or Z isomer or of amixture thereof; provided that 4-methyl-5-phenyl-4-pentenenitrile,2,4-dimethyl-5-phenyl-4-pentenal, 4-methyl-5-phenyl-4-penten-1-ol,4-methyl-5-phenyl-4-pentenal, ethyl 4-methyl-5-phenyl-4-pentenoate and4-(phenylmethylene)-1-hexanol are excluded.
 16. The compound accordingto claim 15, wherein the compound is one wherein R, R² or R³ representsa hydrogen atom or methyl group, R^(1′) represents a hydrogen atom and Xrepresents a CHO.
 17. The compound according to claim 15, wherein thecompound is (4E)-4-methyl-5-(4-methylphenyl)-4-pentenal,(4E)-2,4-dimethyl-5-(4-methylphenyl)-4-pentenal,2,4-dimethyl-5-phenyl-4-pentenal, 4-methyl-5-phenyl-4-hexenal,4-methyl-5-phenyl-4-pentenal or methyl(4E)-4-methyl-5-(4-methylphenyl)-4-pentenoate.
 18. A perfumingcomposition comprising i) at least a compound of formula (I) as definedin claim 11; ii) at least one ingredient selected from the groupconsisting of a perfumery carrier and a perfumery base; and iii)optionally at least one perfumery adjuvant.
 19. The perfumingcomposition according to claim 18, wherein the compound is one wherein:R is an ortho, meta or para substituent of the phenyl ring andrepresents a hydrogen atom or a methyl or ethyl group; R¹ represents amethyl or ethyl group; R² represents a hydrogen atom or a methyl orethyl group; R³ represents a hydrogen atom or a methyl or ethyl group;and X represents a CHO, COOR⁴ or CN group, R⁴ being a methyl or ethylgroup.
 20. The perfuming composition according to claim 18, wherein thecompound is one wherein R, R² or R³ represents a hydrogen atom or methylgroup, R¹ represents a methyl group and X represents a CHO group. 21.The perfuming composition according to claim 18, wherein the compound(I) is (4E)-4-methyl-5-(4-methylphenyl)-4-pentenal,(4E)-2,4-dimethyl-5-(4-methylphenyl)-4-pentenal,2,4-dimethyl-5-phenyl-4-pentenal, 4-methyl-5-phenyl-4-hexenal,4-methyl-5-phenyl-4-pentenal or Methyl(4E)-4-methyl-5-(4-methylphenyl)-4-pentenoate.
 22. A perfumed articlecomprising: i) at least one compound of formula (I), as defined in claim11; and ii) a consumer product base.
 23. The perfumed article accordingto claim 22, wherein the consumer product base is a solid or liquiddetergent, a fabric softener, a perfume, a cologne or after-shavelotion, a perfumed soap, a shower or bath salt, mousse, oil or gel, ahygiene product, a hair care product, a shampoo, a body-care product, adeodorant or antiperspirant, an air freshener, a cosmetic preparation, afabric refresher, an ironing water, a paper, a wipe or a bleach.
 24. Theperfumed article according to claim 22, wherein the compound is onewherein: R is an ortho, meta or para substituent of the phenyl ring andrepresents a hydrogen atom or a methyl or ethyl group; R¹ represents amethyl or ethyl group; R² represents a hydrogen atom or a methyl orethyl group; R³ represents a hydrogen atom or a methyl or ethyl group;and X represents a CHO, COOR⁴ or CN group, R⁴ being a methyl or ethylgroup.
 25. The perfumed article according to claim 22, wherein thecompound is one wherein R, R² or R³ represents a hydrogen atom or methylgroup, R¹ represents a methyl group and X represents a CHO group. 26.The perfumed article according to claim 22, wherein the compound (I) is(4E)-4-methyl-5-(4-methylphenyl)-4-pentenal,(4E)-2,4-dimethyl-5-(4-methylphenyl)-4-pentenal,2,4-dimethyl-5-phenyl-4-pentenal, 4-methyl-5-phenyl-4-hexenal,4-methyl-5-phenyl-4-pentenal or Methyl(4E)-4-methyl-5-(4-methylphenyl)-4-pentenoate.